Changes in sympathetic activity to heart and blood vessels during desynchronized sleep

Abstract

In mid-collicular decerebrate cats, the activity in sympathetic nerves to the heart, kidney, gastro-intestinal tract, pelvic viscera and blood vessels of skeletal muscle was examined during periods of extensor rigidity and during desyncronized sleep-like periods (DSp) either occurring spontaneously or induced by physostigmine sulphate. during DSp the activity in sympathetic vasoconstrictor fibres to muscle increased whereas that in the other sympathetic nerves decreased. The changes were present in vagotomized and sino-aortic denervated animals as well as in paralyzed preparations. It was concluded that the differential pattern of sympathetic activity was a characteristic of the tonic stage of desynchronized sleep and originated from a site in the central nervous system independently of afferent input.